This invention relates to optical interference filters and more particularly to ion-implanted single or multilayer optical interference filters.
Heretofore optical filters have been made by sputtering or by other methods of depositing materials of differing refractive index onto a transparent substrate. Such structures work well for low-power light application; however, for high-power illumination the deposited films peel-off or crack. Such a structure is found in U.S. Pat. No. 3,962,062 in which the films are deposited by sputtering.
Electrically insulated integrated circuits (U.S. Pat. No. 3,976,511) have been formed by bombarding the surface of a substrate by ions and then heating the resultant bombarded surface sufficiently to react the ions with the substrate. The structure is further formed by depositing a layer onto the ion-bombarded structure and then forming desired patterns of electrically insulating layers thereon. U.S. Pat. No. 3,976,512 also illustrates ion bombardment in forming integrated circuits.